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ORGANIZATION OF THE FOREST SERVICE.
GIFFORD PINCHOT, Forester.
OVERTON W. PRICE, Associate Forester.
P. P. WELLS, Law Officer.
HERBERT A. SMITH, Editor.
GEORGE B. SUDWORTH, Dendrologist.
Grazing.-ALBERT F. POTTER, Assistant Forester, in Charge.
Operation.-JAMES B. ADAMS, Assistant Forester, in Charge.
Accounts.-GEORGE E. KING, Chief.
CLYDE LEAVITT, Assistant Chief.
Engineering.-W. E. HERRING, Chief.
Lands.-GEORGE F. POLLOCK, Chief.
Silviculture.-WILLIAM T. Cox, Assistant Forester, in Charge. Extension.-SAMUEL N. SPRING, Chief.
Silvics.-RAPHAEL ZON, Chief.
Management.-E. E. CARTER, Chief.
W. G. WEIGLE, Assistant Chief.
Products.-WILLIAM L. HALL, Assistant Forester, in Charge.
Wood Preservation.-CARL G. CRAWFORD, Chief.
PRODUCTION OF RED CEDAR FOR PENCIL WOOD.
One of the most common articles in everyday use is the lead pencil. Something like 315,000,000 pencils are manufactured in the United States each year, and the industry is steadily growing. In the manufacture of these 315,000,000 pencils there are required. 109,000 tons or 7,300,000 cubic feet of wood, so that each day in the year 300 tons or 20,000 cubic feet of wood are used for pencils. By far the greater part of this wood is red cedar. Its softness, straight grain, and freedom from defects render it peculiarly adapted to the purpose, and a suitable substitute has never been found. Indeed, it is doubtful if any other wood-using industry is so dependent upon a single species as the pencil industry is dependent upon red cedar. To realize the scarcity of pencil material, it is only necessary to visit the cedar mill yards where are now being used old rails and small and knotty logs, which a few years ago would not have been considered. How long the supply will last is hard to say, but it is certain that some of the mills now in operation must shut down inside of a dozen years, and this regardless of any measures which may be taken in the meantime to protect the young growth.
THE WOOD AND ITS USES.
The requirements for lead-pencil material are very exacting. A soft wood, even and straight grained, free from defects, and one which will not check or warp, is essential. The heartwood of red cedar fulfills these requirements and is, besides, very durable. The quality of the heartwood, however, varies widely throughout the tree's range. Even local conditions influence its texture. As an example of local variation, the heartwood of cedar which grows on hummocks and on low ground is decidedly of better quality than that of trees which grow on the upland. It has a more uniform dark red color, is softer, and contains very little white rot, or "polecat" wood, which occurs frequently in upland cedar. It is said by the pencil companies that the cedar found near its western range in Texas and Arkansas has a flinty texture, which gives it a poor grade and often relegates its use to penholders. Another defect, known as "bird's eye," often occurs in the cedars of both upland and hummocks. This blemish is a small black speck running from heart outward, and is really an old, dormant
HISTORY OF THE OPEN-TANK METHOD.
There have been many attempts to find a cheap and effective preservative process requiring no costly mechanical equipment. Most of these attempts were founded on an unsound theoretical basis, and many of them failed for other reasons. Obviously one of the simplest methods of securing a penetration is to boil the wood in the preservative, and this method has been frequently employed. It was not, however, until the year 1867, when Prof. Charles A. Seely, of New York, discovered and patented the process which bore his name, that the true value of the boiling method was ascertained. Through Seely's attempt to increase the penetration by immersing the timber in a bath of cold preservative after it had remained for some time in the boiling liquid was discovered the principle which later developed into the open-tank method of to-day. Apparently, however, Seely's investigations attracted but little attention at the time, and though some writers assert that his method was used in various parts of the United States, no record can be found to-day of its application on a commercial scale. It appears to have been practically abandoned after a few years.
At the Louisiana Purchase Exposition a series of experiments was undertaken by the Forest Service to determine some practical method of prolonging the life of fence posts. The expense of treating such timbers by the pressure processes was prohibitive; yet the receding of the forests, the agricultural development of the country, and the fencing in of large quantities of grazing lands in the West had depleted the supply of posts for farm purposes and raised their price. In the St. Louis experiments, boiling the posts in a vat containing tar oil was at first attempted, with only fair results, but in the course of the tests to increase the penetration the principle of the method once employed by Seely was revived. Subsequent developments in the experiments in which the Forest Service has applied this principle have resulted in what is now known as the open-tank method.
WHAT THE OPEN-TANK METHOD IS.
As already suggested, the open-tank method is based upon the use of an open tank, capable of withstanding heat, and either equipped with steam coils or so arranged that fire can be placed underneath.
Sufficient preservative is run into the tank to cover the portion of the timber which is to be treated, and the temperature of the liquid is then raised slightly above the boiling point of water. This temperature is maintained for a length of time depending upon the character of the wood and the treatment desired. At the end of the hot bath the timber is either quickly transferred to another vat, containing a cold preservative, in which it is submerged for a definite.